Could someone explain to me why there are some recordings with sample rates as high as 192kHz? If most of us hear up to 20kHz, wouldn't 44.1kHz or even 48kHz be enough? Or is there other practical aspects besides boosting maximum frequency in higher sampling rates I am not aware of?

...but if you're simply relying on the high sample rate to keep processing aliases out of the audible band, you need to go into the MHz for some operations. Or do them in a smarter way. I agree that keeping the base Nyquist limit a little higher when you're resampling through each of many different DSPs can help in an objective and measurable sense: it can mitigate some of the effects of careless processing and/or resampling in each DSP module. This can be audible is the processing is bad enough - e.g. really trashy resampling. But is the improvement enough to turn trash into perfection? No.

C.R.Helmrich's response is right IMO - people do it because they can, and they believe it sounds better. Despite an almost total lack of any corroborating evidence. Plus a few people will pay more for a recording at a higher sample rate, for the same reason.

I guess the question becomes: why wouldn't you do it? If it costs nothing, and sells one more copy, or lets you charge some people more, or gets you bragging rights in some circles, then it's "worth it" - even if the technical benefit is zero.

...but if you're simply relying on the high sample rate to keep processing aliases out of the audible band, you need to go into the MHz for some operations. Or do them in a smarter way. I agree that keeping the base Nyquist limit a little higher when you're resampling through each of many different DSPs can help in an objective and measurable sense: it can mitigate some of the effects of careless processing and/or resampling in each DSP module. This can be audible is the processing is bad enough - e.g. really trashy resampling. But is the improvement enough to turn trash into perfection? No.David.

Sure, but for polynomial equations (or polynomial approximations of transcendental functions), the aliasing is predictable. Because multiplying two signals M and N will produce a sideband at M+N, each polynomial order will require an equivalent increase in sampling frequency. Certainly there are other aliasing-reducing techniques such as using an all-pass for fractional delays and minBLEP for waveform generation, but for resonant IIR filters, especially, the higher sample rate can really make a difference (and admittedly most plugins probably upsample/downsample internally)

Note that I'm not at all trying to imply that high sample rate in final, delivered, consumer audio is justified. I'm just pointing out that doing the mixing and production at high sample rate is worthwhile. And if you already have a 192kHz master, why not try to sell it for a few bucks more?

And if you already have a 192kHz master, why not try to sell it for a few bucks more?

Because you don't want to make your money by fooling people?

It's retailing. It's based on fooling people, and people want to be fooled. They want to believe expensive food tastes better, for example. They want to read about all the reasons it tastes wonderful. The sunshine in the fields. The beautiful maidens who picked each crop by hand. Reading about all those reasons will make the food taste better to them - even though none of those reasons changes the actual taste of the food at all.

The biggest problem IMO is when there's only fooling, and real progress disappears where it might otherwise have been possible and beneficial. Also, where outright lies are told.

I don't mind a free market where several quality levels are offered; I can try them, and pay for the one I find acceptable.

I know certain people will claim that they hear differences I cannot. However, with all these quality levels available, I can set up rigorous ABX testing

Anyway, back to reality: if you are making high quality recordings, and some of the people purchasing your high quality recordings want to pay you $10 extra for a 192kHz version, why on earth wouldn't you make one available? As long as it doesn't make the quality worse, and doesn't cost you more than the financial return, it's really not a problem if people want to pay more for no tangible benefit.

I think it should be quite clear to anyone here that it's of no audible benefit what-so-ever, but it may create an excuse (that the accountants will accept) to create better (re-)masters. Which will then be used for the 44.1kHz version that can now be bought for a bargain price. Everyone's a winner.

Does this explain why parts of the industry are heading down this route? And those who should speak out, don't? Granted, it could be The Emperor's New Clothes all over again, but I suspect many people know exactly what they're doing.

The downside is that we don't get proper surround. Though some people are still quietly working on that too.

The downside is that we don't get proper surround. Though some people are still quietly working on that too.

I'm intrigued by this part...how does industry support for silly sample rates keep us from getting proper surround?

There's only so much effort, marketing, messaging etc - and the parts of those aimed at "better sound" are mostly going the wrong way IMO. Resources, and audiophile's attention, are not infinite.

Or to put it another way, they've got to sell something. They've chosen to sell imagined improvements, rather than real ones, a) because it's easier, and b) because plenty of people who should know better haven't called "foul".